Brake for sanders



June 4, 1929. B, D; PINKNEY 1,715,385

BRAKE FOR SANDERS Filed Jan. 6, 1927 2 7l [f/ d C I ANVR/vf Vs.

Patented `lune 4, 1929.,

" Utr su s Ferca.

BRYAN I). PINKNEY, OF SMITHVILLE, NEW JERSEY, ASSIGNOETO I-I. B. SMITH MA- CHINE COMPANY, OF SMITHVILLE, lNEVI JERSEY, A. CORPORATION OF NEW" JERSEY.

BRAKE non SANDERS.

Application :nea January e, 1927. serial no. 159,270.1

My invention relates to an improvement in sanders and more particularly to the provision of novel means for braking the sanding drums.

Heretofore inthe use of Sanders of the type including one or more rotating drums to which my invention more particularly relates, considerable diliculty has arisen from the fact that the drums which are rotated at relatively high speed arel diflicult to stop when it is desired to stop them, since they have considerable momentum and no practical device in the nature of a brake has heretofore been provided.

Now, it is the object of my invention to provide braking means which when applied to a sander will be eiicient to stop the drums and which may be operated by a single lever to brake a plurality of drums, the braking means for each drum being so arranged and actuated as to conform to the characteristics of the drums respectively, so that none of the drums will be excessively braked and all will be quickly and evenly brought to rest.

Having now indicated, in a general Way, the nature and purpose of my invention, I will proceed to a detailed description thereof with reference to the accompanying drawings in which there is illustrated a preferred embodiment and in which Fig. 1 is a cross sectional view, partly broken away, of a sander embodying my invention.

Fig. 2 is a sectional view on line 2 2, Fig. l.

In the drawing a indicates the frame of the sander, which may be of any usual construction, supported in ball bearings Z). Mounted in the frame, are shafts o, upon which are mounted sanding drums d.

On one end of each of the shafts c is a disc e, opposite to which is a disc f mounted on the end of the shaft g of a motor 7L, mounted on a base z' supported by means of brackets y' extending from frame a. The discs f and e, secured to the motor shaft and the sanding drum shaft respectively, are connected by means of a flexible driving connection of any desirable type positioned Within a casing la.

Extending lengthwise beneath the discs f is a rod Z, one end of which is pivotally connected to a hand lever m pivotally secured to a bracket n at one end of the motor base The rod Z passes through holes in brackets o securedto the ends of brake bands p, suitably faced with brake lining g. Y The brake bands are supported adjacent the surfaces of discs f by means ofbraekets r secured to the motor base z' and provided withy pins s,

which extend into eyes formed at theendsof the bands.` y

The rod Z is threaded for a distance adjacent the several brackets 0 and carries coil springs Z which abut against the brackets and are restrained by nuts .u threaded on the rod, and by which the tension of the springs t may be adjusted.

In the operation of the device embodyin my invention, if it be desired to stop the drums, the current is cut off from the motors and the lever m is pulled by the operator causing, as will be obvious, a longitudinal movement of rod Z, which results in a compression of springs t which react on the brackets o and cause the bands p to be swung on the pins s up against the surface of discs f.

The distance which lever m is moved determines to a certain extent the degree of pressure of the band-s on the discs and hence the braking effect, but it will be observed that the movement of lever m and rod Z is transmitted to the bands through springs t, which act resiliently to force the bands against the dises. Since the power applied to the bands is applied through resilient means, the springs t, any difference in the adjustment of the several bands will be automatically compensated for and sudden stopping of any drum will be`.avoided,`since any tendency of a band to bind will be avoided due to the capacity of the spring not only to transmit power to the band for its application, but to permit the band to slack off it, due to irregularities of a drum or other cause, the power .applied by therlever lml be excessive for any given drum.

Having now fully described my invention, what I claim and desire to protect by Letters Patent is 1. In combination, a plurality of rotary shafts, brake bands associated with said shafts, a brake rod and resilient means affording connections between said rod and said' bands respectively.

2. In combination, a plurality of rotary shafts, discs carried by said shafts, brake bands pivotally supported at one end adjacent the peripheral surfaces of said discs, a brake col rod and springs aii'ording an operative connection between said rod and said bands respectively.

3. In combination, a plurality of rotary shafts, discs carried by said shafts, brake bands pivotally supported at one end adjacent the peripheral surface of said discs respectively, brackets on said bands, a rod extending through apertures in said brackets, springs on said rod adjacent to said brackets and stops carried by said rod and positioned to confine said springs against said brackets whereby said springs will aord a resilient connection between said rod and said bands,

4.- In combination, a frame, a plurality of rotary sha'ftsvmounted in said frame, brake drums carried by said shafts, brackets secured K to said frame adjacent tosaid drums, brake bands pivotally s upported from said brackets, brackets on said brake bands, a rod extending through apertures formed in said brackets on said bands, said rod being threaded for a distance adjacent each of said last nientioned brackets, springs onsaid rod positioned adjacent said last mentioned brackets, nuts threaded on said rod and adapted to confine said springs against said last mentioned brackets and a lever pivotally supported from said frame and connected to said rod whereby said rod maybe actuated for the application of said bands to ysaid brake drums l through the medium of said springs.

In testimony of which invention, I have hereunto set my hand, at Smithville, New Jersey, on this third .day of January, 1927.

BRYAN D. PINKNEY. 

